CTLA-4 gene polymorphism in promoter and exon-1 regions in Chinese patients with systemic lupus erythematosus.

Cytotoxic T lymphocyte associated antigen 4 (CTLA-4), a structural homologue of CD28, has been reported to be an important negative regulator of autoimmune diseases. Recent studies showed that CTLA-4 gene polymorphism was associated with several kinds of human autoimmune diseases, suggesting that CTLA-4 gene is probably a general susceptibility gene to autoimmune disease. The present study was conducted in Chinese to determine whether there is any association of the CTLA-4 gene polymorphism with the development of systemic lupus erythematosus (SLE). CTLA-4 gene polymorphism in promoter and exon 1 was detected by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method in 81 patients with SLE and 81 normal controls. The results showed that there were no statistically significant differences in both exon 1 and promoter gene polymorphism between SLE patients and normal controls. The preliminary study does not suggest an association of the known polymorphism in exon 1 and promoter of CTLA-4 gene with Chinese SLE. However, SLE is a very heterogeneous syndrome and CTLA-4 gene polymorphism might correlate with some specific clinical features. To exploring this possibility, subgroup analysis in more patients needs to be performed.